The Art of Slow Dovetailing—Lap Dovetails Introduction In a previous article I talked about the art of slow dovetailing in relation to cutting though dovetails. A contemplative approach to hand dovetailing where the emphasis is on doing the job well rather than quickly. Dovetailing is about method and attention to detail. In this article we will bring the same approach to cutting lap dovetails. Lap dovetails are usually found on the fronts of drawers. The dovetails on the sides do not extend right through the drawer front, there is a lap of about 4-6mm which preserves the line of the front. This means we cannot cut the pins in the front piece in the same way as we did for though dovetails, instead we have to saw part of the way then resort to the chisel. Getting nice clean sockets between the pins is the tricky bit! If you haven’t done so already it may be worth reading the through dovetailing article before tackling lap dovetails. This article is developed from the hand out for my basic skills part III course where we cut both through and lap dovetails whilst making two sets of book ends.
Naming of parts
Lap dovetails—marking the tails Firstly ensure your pieces are planed up true with face side and edge and also clean square ends. The joint should be arranged so the face edges are adjacent and the face sides are on the inside. Lap dovetails do not extend the whole width of the pin piece, there is usually a margin of 4 or 5mm at the front. To mark the shoulders determine the length of the tails, set the cutting gauge to this and mark the tail shoulder round the end of the tail piece . This should also be marked on the end face of the pin piece. Reset the gauge to a millismidgeon less than the tail piece thickness and mark the pin shoulders as with a through dovetail.
Setting the gauge to mark pin length.
Marking the tails.
Marking pin length.
Having gauged the shoulders of the shorter dovetails the marking and cutting of the tails is the same as for through dovetails.
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Mark and Saw the Pins The pins can be marked from the tails in a similar way to a through dovetail, the front of the tail piece will align with the gauge line on the end of the pin piece. The spaces between the pins cannot be sawn in the same way as through dovetails, instead we have to do a diagonal saw cut to define the shape of the pins then chop out the waste with a chisel. The position of the saw cut on the waste side of the line is very important.
Marking pins using the tails as a template.
Start the cut on the front corner on the waste side of the line and make an angled cut that follows the slope of the pin and stops at each corner of the tail socket. Sometimes it can be useful to make repeated cuts in the waste to aid chopping out later. However you have to be careful you chop away the right pieces as thin pins can look like waste!
Diagonal saw cut to cut the pins.
Showing the position of the cut on the waste side of the line.
Main cuts complete.
Additional cuts to allow easier removal of waste.
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Chop out the waste between the pins Start with the piece clamped flat on the bench and chop down a few millimetres from the end and work your way back to just short of the gauge line chopping down about 2-3mm. Now take a horizontal cut to remove the waste loosened by the earlier cuts. Repeat this process until you approach the gauge line on the end. Try to keep the faces tidy so you can see what’s going on. This is helped if you make sure you have chopped through the grain fibres before making a paring cut with the grain.
Starting to chop away the waste.
When there is just a slither left you can place the chisel into the gauge lines to chop or pare away to the line in both directions. Once you have cut back to the lines put the piece upright in the vice and clean up the sides of the pins , there will be a diagonal area of waste, cut this back to flush with the original saw cut, using the saw cut as a datum for the paring. A pair of skewed chisels will help you to get into the corners. Continue paring until the recess is square or slightly undercut. A combination square is good for checking this. The one shown is one of my favourite tools (sad but true!).
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Assemble the joint and check the fit. Before assembling it is worth paring the inside edges of the tails as we did for though dovetails. You are more likely to have issues with untidy corners with laps than with through tails, this paring could be extended round to the inside ends of the tails. Again be careful you pare the right corners as paring in the wrong place can spoil the joint. An additional consideration when fitting a lap joint is the fitting of the ends of the tails against the lap. Sometimes if the lap slopes into the recess pushing the joint home has the effect of pushing the tails away from the lap to leave a gap at the end of the tail. It’s not easy top show this in a photograph! Checking the laps are square to the shoulder using a combination square can help here. When you are happy with the joints dry fitted go ahead and glue up. You will remember that we set the gauge for marking the pin lengths a millismidgeon less than the thickness of the dovetail piece. This should mean that the pin ends sit slightly below the surface of the tail piece. This makes clamping up easier. A light planing after glue up should flush off the joint.
Paring the inside edges of the tails.
Conclusion From reading this you can probably tell that cutting lap dovetails takes longer than through dovetails. You need very sharp chisels! If you are working at chiselling out the sockets and finding it difficult , don’t assume it’s your incompetence, try sharpening the chisel! In a subsequent article I will show how to remove the waste with a router, not quite slow dovetailing, but if you have a set of drawers eight to dovetail I think you might consider it!
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